BGP default route propogation

[jwtheiss57]

I have several sites (site A, B, C, D, Z) connected via BGP in a hub/spoke configuration where site Z is the hub. Each site's only neighbor is site Z (the hub).I have default routes configured on sites A & B pointing to their respective Internet connections. Is it possible to configure a

conditional default route on A pointing to site B only should site A's Internet connection go down.

[Akash Agrawal]

Hi,

I believe when you are originating default route at site A and B, then you will advertise same to hub Z and Z will advertise to other spoke sites. So site A would also have default from site B, but it will prefer default pointing towards ISP if ISP is up (not sure if you are receiving default from ISP or have put static route). When ISP link goes down, site A will prefer bgp default route coming from site B.

If your design is different from this, please correct me

Regards,

Akash